RM0440 Rev 4 1263/2126
RM0440 General-purpose timers (TIM2/TIM3/TIM4/TIM5)
1343
Note: For 16-bit timers, the maximum TIMx_ARR and TIMxCCRy values are limited to 0xFFFEF
in dithering mode (corresponds to 65534 for the integer part and 15 for the dithered part).
For 32-bit timers, the maximum TIMx_ARR and TIMxCCRy values are limited to
0xFFFFFFEF in dithering mode (corresponds to 264435454 for the integer part and 15 for
the dithered part).
As shown on the Figure 392 and Figure 393 below, the dithering mode allows to increase
the PWM resolution.
Figure 392. PWM resolution vs frequency (16-bit mode)
Figure 393. PWM resolution vs frequency (32-bit mode)
The duty cycle and / or period changes are spread over 16 consecutive periods, as
described in the Figure 394 below.
MSv47464V2
PWM resolution
16-bit
PWM frequency
F
PWM
min
Dithering
No Dithering
20-bit
MSv50912V1
PWM Resolution
32-bit
PWM frequency
F(cnt) min
No dithering
F(cnt) min
with dithering
DitheringNo Dithering